Build a working clone of the vintage KIM-1 6502 microcomputer
We live in a world of highly complex electronic devices that make our lives a lot simpler, by hiding the way that they are programmed or controlled. Of course this is great, however for the more technical among us it doe insulate us from how things really work.
To get back to the roots of our computers and gadgets, it can help to travel back in time (not literally... but if you can do that, please let us know) and examine computers from the previous century to see how they work.
One fascinating example of this is the KIM-1 computer, a very simple computer based on the 6502 microprocessor in 1976, as shown below:
The KIM-1 was programmed in assembly language, and later on with BASIC and may have been the inspiration behind other designs of the time using the same 6502 CPU, such as the Apple computer.
To revel in this nostalgia and also have some fun, you can now make your own KIM-1 replica quite easily thanks to a project published by Oscar at the Obsolescence Guaranteed website. They have deconstructed the original and published all the details on how to reproduce your own KIM-1 based on an Arduino Pro Mini-compatible board.
Apart from emulating the KIM-1, the extra memory in the host Pro Mini board is used to hold the code for a calculator and a simple chess game. Furthermore the internal EEPROM on the microcontroller can be used as non-volatile storage (1024 bytes is better than nothing!). After having the PCBs made by your favourite fab, assembly is quite straight forward and would make a neat afternoon project.
In order to make your own version of the KIM-1 using Oscar's design, you will need the following main parts:
- Arduino Pro Mini-compatible board
- lots of tactile buttons
- FTDI to USB adaptor to upload code to the Pro Mini and also connect with a PC for terminal emulation
Then for a complete description to make your own, including code and PCB files - visit Oscar's fascinating website.